The disclosure is directed generally to heat exchangers, and more specifically to manifolds for heat exchangers.
Heat exchangers that operate at elevated temperatures, such as those in modern aircraft engines, often have short service lives due to high steady state and cyclic thermal stresses. Inlet and exit manifolds are typically pressure vessels that are welded or bolted at only the exterior perimeter to a heat exchanger core or matrix. Pressure requirements dictate the thickness of these manifolds, usually resulting in a relatively thick header attached to a thin core matrix. This mismatch in thickness and mass, while acceptable for pressure loads, conflicts with the goal of avoiding geometric, stiffness, mass and material discontinuities to limit thermal stress.
Further, air flow distribution from conventional open manifolds can be very non-uniform, depending on core pressure drop, flow velocity, and orientation and size of the ducts. The core is therefore not fully utilized, and in some cases the hot circuit and cold circuit flows can largely miss each other.